Bianca Andreescu

Andreescu has not played since injuring her knee in her match against Karolina Pliskova at the WTA Finals at the end of October.

She pulled out of the Auckland Classic and then the Australian Open as her start to 2020 was delayed by her recovery, having also struggled with a host of other injury issues last year.

Andreescu is in Biel with her Canada team-mates for the Switzerland tie, which will be played over February 7 and 8.

World number five Belinda Bencic, who Andreescu beat in the semi-finals at Flushing Meadows, is one of her possible opponents this week.

"She has been training and she is improving every day – we are taking it day by day," said Canada captain Heidi El Tabakh.

"We know that, for this tie, time is against her, but she's been making a lot of improvements.

"She still has a couple of days left. As of right now, we haven't made any decisions yet about the team, but we will when the time comes."

Andreescu told Tennis Canada: "I think there's still a chance. We haven't made any decisions yet but I'm hoping I can play."

Switzerland are preparing as if Andreescu will play in the tie, which is one of eight contests which will decide the teams to join Australia, France, Czech Republic and Hungary for the inaugural Fed Cup Finals in Budapest in April.

"I have to assume Bianca Andreescu is going to walk out there and compete because why else would she be here?" said Switzerland captain Heinz Guenthardt.

"Nobody knows how well she'll compete - probably even she doesn't know that.

"It's a different thing to practice and then walk out there and play a Fed Cup tie. 

"It doesn't sound like a very thought out answer, but in the case of this week particularly we're just going to try to focus on ourselves.

"We have a good group. Belinda is obviously our number one and then we have four players who can on their given day represent Switzerland."

The qualifying round contains some impressive line-ups, with Serena Williams, Australian Open champion Sofia Kenin and teen star Coco Gauff among the United States team playing Latvia, while Naomi Osaka leads Japan against Spain.

Despite making a strong start, fourth seed Pliskova faltered and lost 1-6 6-4 6-4 to the world number 127 in the pair's last-32 match.

Boulter said: "I'm super-proud of myself today. I went out there and didn't feel great on court, and I worked so hard to battle and fight, and against a player like that it means so much to me, coming through that."

There was another major shock win for a British player later in the day as Jodie Burrage knocked out top seed Paula Badosa, the world number 169 triumphing 6-4 6-3 against a player who will be seeded fourth at Wimbledon.

Defending champion Jelena Ostapenko beat Ajla Tomljanovic 6-4 6-4 and two-time Wimbledon winner Petra Kvitova saw off Donna Vekic 6-1 7-6 (7-1), while Beatriz Haddad Maia's strong form on grass continued with a 6-4 3-6 6-3 victory over Estonian veteran Kaia Kanepi.

Brazilian left-hander Haddad Maia is coming off the back of title wins in Nottingham and Birmingham and stretched her winning run on grass to 11 matches.

There were also wins in Eastbourne for Camila Giorgi, Madison Keys and Barbora Krejcikova, but Greek third seed Maria Sakkari bowed out, losing 3-6 7-5 6-4 to Ukrainian Anhelina Kalinina.

At the Bad Homburg Open in Germany, the 2019 Wimbledon champion Simona Halep scrambled for a 4-6 6-3 6-4 win against Katerina Siniakova, and sixth seed Amanda Anisimova came from a set down to see off Alison van Uytvanck in a third-set tie-break.

Bianca Andreescu saw off Martina Trevisan 6-3 6-1 and Angelique Kerber also won in straight sets, while top seed and recent French Open semi-finalist Daria Kasatkina reached the quarter-finals with a 6-1 3-6 6-1 win over Germany's Jule Niemeier.

Kasatkina will be absent from Wimbledon due to the ban on Russian players.

With both players having to play two matches in one day, Pliskova started strong, powering through the first set in just 39 minutes before the the physical toll started to kick in.

Boulter found her second wave though, fighting back to force a decider in which she broke the Czech's serve three times to seal the victory.

It was a long day for Boulter, who came out on top in an all-British semi-final earlier in the day against Emma Raducanu in three sets after their semi-final was suspended on Saturday due to bad weather.

Raducanu won the first set after 80 minutes in a tie-break, but she could not pick up where she left off on Sunday, as Boulter came from behind to win 6-7 (13-15) 6-3 6-4.

Meanwhile, Liudmila Samsonova won her first title of the season after also coming from a set down to defeat Bianca Andreescu 4-6 6-3 7-5 in the Libema Open final at 's-Hertogenbosch.

Data Debrief: Boulter powers through marathon day

Boulter and Pliskova had split their first four meetings, and all five of their matches have gone the distance to a decisive third set.

The Briton won 77 per cent of her service games (10/13), while also winning 43 per cent of her return games (6/14), double the amount of Pliskova.

Andreescu has not played on the WTA Tour since October due to knee trouble and the 20-year-old says a lack of match practice, partly due to the coronavirus pandemic, means she is not ready to return in New York.

The Canadian's withdrawal comes after Rafael Nadal, the 2019 men's singles champion, pulled out due to the COVID-19 crisis.

Andreescu posted on social media: "After many discussions with those closest to me, I have made the difficult decision not to return to New York this year.

"I have taken this step in order to focus on my match fitness and ensure that I return ready to play at my highest level.

"The US Open victory last year has been the high point of my career thus far and I will miss not being there.

"However, I realise that the unforeseen challenges, including the COVID pandemic, have compromised my ability to prepare and compete to the degree necessary to play at my highest level.

"I want to express my appreciation to the USTA and the WTA for all of their efforts in making the event happen. I look forward to joining my competitors back on court soon."

Williams has won none of the past 13 majors, dating back to her most recent success at the 2017 Australian Open, though she missed the first four of those having given birth.

This is the 23-time champion's longest stretch without a grand slam win since she made her Melbourne bow in 1998.

Williams has reached at least the semi-finals in five of her past eight major appearances, yet she has not recorded a win in that time and, having not made the Roland Garros quarter-finals since 2016, an end to that miserable run appears unlikely in the coming weeks.

So could the future of the women's game be present in Paris? Well, finding Serena's heir is proving rather difficult.

While she is one of seven female players to have claimed 10 or more major titles, Serena is the only member of that elite group to have won a championship in the 21st century.

Justine Henin and Serena's sister Venus have each had seven wins, yet other genuine rivals have been a rarity over the past 20 years.

Roland Garros results have illustrated this trend as well as any championship. Only Serena, Henin and Maria Sharapova have won multiple French Open titles since the start of the 2000 season, with Henin's 2005-2007 run the last time a woman celebrated consecutive triumphs on the red clay.

That drought will continue for at least another year, too, due to Ash Barty's absence.

Another name missing from this year's draw is perhaps the most likely candidate to emulate Williams' success. US Open champion Naomi Osaka is still just 22 but has won three of the past seven majors she has contested. That also amounts to just three victories in three seasons, but time is on her side as she looks to shape her own legacy.

Williams is Osaka's idol, as was so painfully evident when the Japanese shed tears following a grand slam breakthrough that came during Serena's 2018 US Open meltdown. The pair watched one another at Flushing Meadows earlier this month, although Serena's last-four defeat prevented a highly anticipated final rematch.

"I feel like she's such an intense player that is really exciting to watch," Williams said of Osaka, who looks to have adopted her role model's single-minded drive.

Discussing her impressive grand slam record prior to this month's victory over Victoria Azarenka, Osaka revealed her approach: "No-one remembers anyone but the winner."

Yet Osaka has work to do if she is going to be a winner on all surfaces like Williams, one of just two players - along with Sharapova - to win a career Grand Slam since the turn of the century. Angelique Kerber could join that club in the coming weeks, yet French Open success seems increasingly unlikely for the two-time quarter-finalist and world number 22. Osaka has not been past the third round at Roland Garros or Wimbledon, reserving her success for the hard courts.

Meanwhile, although victory at the Australian Open in 2019 quickly added to Osaka's first triumph, that second title has proved tricky for a number of other hopefuls.

Since Serena's 23rd major honour, six women have become one-off grand slam winners - including Sofia Kenin, 21, and Bianca Andreescu, 20. The pair are younger than several other champions, yet neither have even reached a quarter-final outside of their sole successes.

Andreescu has seen her 2020 season completely wrecked by injury and withdrew from Roland Garros this week. In her stead, others will look to join her as a champion. Qatar Open winner Aryna Sabalenka, Elena Rybakina and last year's French Open finalist Marketa Vondrousova are each younger than Osaka and hold a place in the WTA's top 20.

Then, of course, there is Coco Gauff, ranked 51st.

The 16-year-old beat Venus at both the 2019 US Open and the 2020 Australian Open, also eliminating defending champion Osaka at the latter. At each tournament, she lost only to the eventual winner.

"She clearly wants it, works very hard, is extremely mature for her age," Venus said. "I think the sky's the limit for her."

But a first-round exit at the US Open represented a reality check for Gauff. With no Barty and no Osaka, might she seize the opportunity and bounce back in stunning style at Roland Garros?

Or is this Serena's time? Number 24 at last. It is up to the next generation to ensure she cannot afford to keep passing up such chances.

Swiatek clinched her maiden grand slam – and first senior career title – at Roland Garros in 2020, and the Pole was in supreme form as she confidently saw off close friend Juvan 6-0 7-5.

A champion in Rome in the lead-up to Roland Garros, Swiatek made it 20 game wins in a row – dating back to her Internazionali d'Italia semi-final against Coco Gauff – until Juvan held her own in the second game of the second set.

Swiatek saved two break points at 5-5 before wrapping up the win.

"It's never easy to play against your best friend," Swiatek said after the match. "I have some experience because I played with Kaja for a few times. I've played with my other friends on junior level.

"You just try to block this friendship for two hours, just focus on the game.

"I think I'm doing that pretty well. It's nice to have that skill. So I was just trying to treat Kaja as any other girl, as any other opponent, because in sports when we are on court you can't have thoughts that are you going to make your game softer."

ANGUISH FOR ANDREESCU 

There was no such route through for Bianca Andreescu, the sixth seed coming unstuck against world number 85 Tamara Zidansek.

Andreescu's stint at this year's French Open lasted three hours and 20 minutes, but the world number four could not find a way through and duly became the biggest women's casualty of the first round so far.

The 2019 US Open champion headed into the tournament on the back of pulling out of a quarter-final at the Internationaux de Strasbourg due to an abdominal injury and was playing in only her third tour-level match on clay. She won the opening set on a tie-break, yet it was Zidansek who prevailed 6-7 (1-7) 7-6 (7-2) 9-7 to claim her first win over a top-10 opponent.

Kiki Bertens was another seed to drop out, the number 16 going down 6-1 3-6 6-4 to Polona Hercog.

KENIN BATTLES ON

World number five Sofia Kenin saw off a tough challenger in the form of 2017 Roland Garros champion Jelena Ostapenko.

"I knew it was gonna be a tough match, she's a great player," Kenin said, after a 6-4 4-6 6-3 victory. "I knew I needed to play my best tennis in order to win."

Kenin, 22, came from a break down twice to take the opening set, and though Ostapenko hit back, American Kenin held her nerve in the decider, setting up a second-round tie with compatriot Hailey Baptiste.

"I'm a feisty kid, and I have to fight in order to win," added Kenin, who lost to Swiatek in last year's final but has struggled for results in 2021. "I've got a little bit of feistiness in me and that helps me in these types of matches."

The French Open is rich in promise as the Roland Garros clay courts are swept in anticipation of the greats of tennis stepping out to begin their campaigns.

It has been the women's draw that has looked the most wide open in recent seasons, yet this year it is hard to look beyond Swiatek; however, the men's title battle promises to provide a sensational battle.

Here, Stats Perform assesses the contenders for the two main trophies: the Coupe des Mousquetaires and the Coupe Suzanne Lenglen.

KID INTERRUPTS G.O.A.T. RACE

Nadal took full advantage of Djokovic and Roger Federer being absent from the Australian Open, carrying off his 21st grand slam title to go top of the men's all-time list, one ahead of those two great rivals.

Federer is again missing, rehabbing after knee surgery, and the likelihood is he has played his final major already, but Djokovic is emphatically back. His confidence is surging once more, having taken a knock amid the drama of his deportation from Australia in January and being frozen out of the Indian Wells and Miami events due to the United States' COVID-19 rules.

A semi-final run in Madrid, where he lost a three-set monster to Alcaraz, was followed by Djokovic carrying off the Rome title for a sixth time when he saw off Stefanos Tsitsipas in the final.

Djokovic turns 35 on Sunday, as main-draw action gets under way in Paris, but he is the defending champion and firmly believes he can succeed again.

Assessing his prospects for Paris, Djokovic said after his Rome triumph: "With rankings and the way I've been playing in the last few weeks, I would rate myself as one of the favourites. I don't obviously spend too much time thinking who's going to win it or who might have the best chance. I always think about myself.

"I go there with the highest ambitions. I really like my chances. Best-of-five, you play every second day. It's a grand slam. It's different. Really, the grand slams are played different. You have to approach it differently. But the way I've been feeling on the court and off the court in the last few weeks, I really think I can go far."

The chief threat to Djokovic could come not from 'King of Clay' Nadal, but from the 13-time champion's fellow Spaniard, 19-year-old Alcaraz.

Bidding to become the first teenage winner of the men's title since Nadal, also 19, triumphed for the first time in 2005, Alcaraz arrives in Paris with four titles already secured this year, including three on clay in Rio, Barcelona and Madrid. The other title came on hardcourt at the Masters 1000 event in Miami, and Alcaraz has rocketed from 32nd at the start of the year to number six in the world rankings.

Many expect his grand slam haul to reach double digits, just like the Big Three he has grown up watching and learning from. The first slam must come somewhere, and it might well come in Paris in a fortnight's time.

Don't discount Nadal, but his form has been a shade unconvincing since coming back from a rib injury, while Tsitsipas looks the next most likely after winning on clay in Monte Carlo and finishing runner-up to Djokovic in Rome. The Greek has unfinished business in Paris, after the heartache of losing last year's final from two sets up.

IGA TO PLEASE? POLE GOES FROM SHOCK WINNER TO FIRM FAVOURITE

The first thing to point out is that the French Open women's singles title has been won by eight different players in the last eight years.

Iga Swiatek was a surprise champion in 2020, at the tournament that was delayed until the Paris autumn due to the pandemic. She was ousted by Maria Sakkari in the quarter-finals last year but returns on a roll, having won an incredible five consecutive tournaments.

The 20-year-old has won 38 of the last 39 sets she has contested, the odd one out going against her on a tie-break, and her winning streak has reached 28 matches. Since Ash Barty retired, nobody has been able to lay much of a glove on Swiatek.

If she wins the French Open, that run will reach 35 matches, equalling the longest run in the 2000s, previously achieved by Venus Williams during a glory run that saw her win events including Wimbledon, the Olympic Games and US Open in the year 2000.

Tunisia's Ons Jabeur has been spoken of as a possible challenger to Swiatek, but she was swatted away 6-2 6-2 by the youngster in the Rome final last weekend.

So who challenges the favourite? Even those who have been there and done that struggle to look beyond Swiatek. According to Martina Navratilova: "You can’t be any hotter than she is right now."

Navratilova told the WTA website: "She looks pretty unbeatable on any surface, particularly the clay now."

The last player to beat Swiatek was Jelena Ostapenko, in Dubai. Ostapenko, a surprise 2017 French Open champion, had a sizzling spell of form in February but has gone off the boil since. It might take someone of her hard-hitting nature to knock Swiatek out of her stride, though, so if Ostapenko can navigate the early rounds she becomes a real contender. The Latvian's career record against Swiatek? An impressive 3-0.

Who else? Simona Halep's coaching tie-up with Patrick Mouratoglou – Serena Williams' former coach of long-standing – has raised eyebrows and now it might be time for it to raise her results level too. Halep has won in Paris before, in 2018, so don't count her out.

Aryna Sabalenka, Sakkari, Paula Badosa. Such players come into the mix if Swiatek slips up, but there has been scant sign of that happening.

Halep's last grass-court match was the impressive 6-2 6-2 defeat of Serena Williams in the 2019 Wimbledon final.

While Monday's triumph may not have been of comparable importance, the 6-1 6-4 win was a positive step in Halep's preparation for a return to SW19 later this month.

After saving three break points in the very first game, the former world number one rarely looked in trouble against her Ukrainian opponent, breaking Tsurenko's serve at the first opportunity.

She repeated the feat to go 5-1 up before serving to love to close out the set, though Tsurenko showed a bit more fight at the start of the second – only one of the first five service games was a hold.

Halep ultimately weathered the storm, however, taking her chance to go 5-4 up and once again served to love to wrap up the match.

Seeded second, Halep was the only seed in action on Monday and will meet home favourite Harriet Dart next, with the Brit impressively seeing off Camila Osorio – ranked 45 places better off – 6-2 6-0.

In Berlin, fourth and sixth seeds Karolina Pliskova and Daria Kasatkina secured their passage to the last 16.

Pliskova struggled initially against Kaia Kanepi but went on to produce two near-flawless sets to progress 6-7 (6-8) 6-0 6-0 – Kasatkina also came from behind, with an ankle injury to Anhelina Kalinina potentially aiding her 5-7 6-3 6-1 victory.

Bianca Andreescu was also among the winners in Berlin, with the Canadian beating Katerina Siniakova to claim only her second career success on grass.

The 2019 US Open champion has not played a competitive match since sustaining a knee injury during the WTA Finals last October.

Andreescu's agent had already confirmed her withdrawal from the French Open, with the main draw due to begin on Sunday.

And in a post on social media, Andreescu wrote: "I have come to the difficult decision to skip the clay-court swing this year and will be taking the remainder of the season off to focus on my health and my training.

"As hard as it was to come to this conclusion, I have so much to look forward to in 2021, including the Olympics; I want to use this time to focus on my game so I can come back stronger and better than ever.

"As always, all of your encouraging words and support mean the world to me and I look forward to getting back on the court and competing for Canada next year!"

Andreescu became the first Canadian to win a grand slam title when she defeated Serena Williams in the final at Flushing Meadows last year.

She remains number seven in the WTA rankings despite her elongated period of inactivity.

After rain delayed the match on Friday, and start of play on Saturday, a tough battle ensued, but Pliskova reached her third semi-final of the season with a 7-6 (10-8), 7-6 (7-3), 7-5 win.

Pliskova edged the first set on the tie-break before Jabeur forced a decider with an equally impressive win in the second.

Despite going toe-to-toe once more in the third, Pliskova just did enough to hold off top-seed Jabeur, getting a vital break to set up a meeting with Diane Parry.

Meanwhile, Emma Raducanu advanced to her first semi-final since 2022 after receiving a walkover from Francesca Jones, but her match against Katie Boulter was suspended due to rain after the first set, which lasted an incredible 80 minutes.

In 's-Hertogenbosch, Bianca Andreescu will play in the Libema Open final after her straight-sets 6-4, 6-2 victory over Dalma Galfi on Friday, earning a place in her first final of the season.

Data Debrief: Jabeur unable to stop the break

Jabeur had the opportunity to win seven break points during the quarter-final, but had a measly 14 per cent conversion rate (1/7). Pliskova, meanwhile, won half of hers (2/4).

The Czech also won 94 per cent of her service games (17/18), just one more than Jabeur. It was the fine margins that won out in Nottingham.

Qualifier Varvara Gracheva earned her first career top-five win by beating 2022 Wimbledon and US Open finalist Jabeur 6-2 6-2 in only 67 minutes.

Fifth seed Caroline Garcia also crashed out, losing 6-2 6-3 to 74th-ranked Sorana Cirstea, having also recently beaten the Frenchwoman at Indian Wells.

Bianca Andreescu came from a set down to beat seventh seed Maria Sakkari 5-7 6-3 6-4 in a match that lasted over three hours.

Andreescu displayed some of the form that saw her lift the 2019 US Open title, fighting back from a set down and proving composed in the big moments.

The Canadian, who is ranked 31st, will take on 2020 Australian Open champion Sofia Kenin in the third round.

Second seed Aryna Sabalenka had few problems against Shelby Rogers, winning 6-4 6-3 in one hour and 17 minutes. Sabalenka will next face 31st seed Marie Bouzkova.

The 2023 Australian Open champion has won 65 main draw matches in WTA-1000 events, which equals Marion Bartoli and Ashleigh Barty at the 30th place since 2009 for the most wins at this level.

Indian Wells winner Elena Rybakina beat Anna Kalinskaya 7-5 4-6 6-3, and Petra Kvitova eased past compatriot Linda Noskova 6-3 6-0.

Ninth seed Belinda Bencic dropped just two games as she cruised past Leylah Fernandez 6-1 6-1, and will face Ekaterina Alexandrova next as the 18th seed needed three to get past Taylor Townsend.

Veronika Kudermetova was eliminated by Marketa Vondrousova 6-4 6-2, who goes up against Karolina Pliskova in round three after she eased past Wang Xinyu in straight sets.

World number 26 Camila Giorgi battled from a break down in both sets to beat fifth seed Muguruza 7-5 6-3 in an hour and 53 minutes. 

That meant 12th seed Giorgi made her second straight quarter-final, following a last-eight appearance in Birmingham, and will next face Viktoriya Tomova, who defeated Kirsten Flipkens 3-6 6-3 6-4. 

Jil Teichmann, the 10th seed at the tournament, was a notable second-round elimination, falling to a 7-6 (9-7) 4-6 6-3 defeat to Briton Harriet Dart, who later triumphed 6-4 2-6 6-4 over Marta Kostyuk. 

Dart's fellow Briton Katie Boulter stunned last year's Wimbledon runner-up Karolina Pliskova in the second round but had no such luck against Petra Kvitova, losing 5-7 6-0 7-5. 

Beatriz Haddad Maia, the winner at the Birmingham Open last week, extended to a 12-match winning streak with a 6-1 6-2 victory over Jodie Burrage. 

Jelena Ostapenko also progressed after Madison Keys retired when 6-3 down and will next face Anhelina Kalinina, who battled to a 6-3 2-6 6-3 win over 16th seed Yulia Putintseva. 

While seeds fell at Eastbourne, there were not as many shocks at the Bad Homburg Open, where Angelique Kerber defeated Lucia Bronzetti 6-2 6-3 to reach the quarter-finals. 

Fourth seed Simona Halep also made the last eight with 6-0 6-3 victory over Tamara Zidansek and will meet Amanda Anisimova after she won an All-American match against Ann Li 6-0 6-2. 

Alize Cornet downed Tatjana Maria 7-6 (7-4) 6-4 to tee up a clash with Kerber, while Bianca Andreescu will meet top seed Daria Kasatkina after defeating Katie Swan 6-4 6-4. 

Muguruza, who claimed the Chicago Fall Tennis Classic, was surprisingly upstaged 6-3 1-6 6-3 by Australia's Ajla Tomljanovic in an upset on Saturday.

Tomljanovic had been 0-6 against top-10 players this year heading into the match but had just enough to edge the fifth seed and two-time grand slam champion with some timely breaks of serve. 

The world number 47 Tomljanovic is into the third round at Indian Wells for the first time in seven appearances and next faces 26th seed Tamara Zidansek. 

"I was really looking forward to playing Garbine, because I did lose [to her] the last couple of times," Tomljanovic said in her on-court interview. "I did try to focus on that one time I beat her [in 2014], and tried to channel that energy, so I was really happy that I got through today."

GOLUBIC STUNS SAKKARI

Sixth seed Sakkari – a semi-finalist at this year's French and US Opens – also fell victim to a shock result, going out 5-7 6-3 6-2 to Viktorija Golubic in their first meeting. 

The pair kept trading service breaks in the opening set, five in all, before Golubic tightened up her game for the final two sets. 

After breaking the Swiss three times in the first set, Sakkari converted just one of four break points the rest of the match. 

Golubic had lost in the first round in her previous two trips to Indian Wells but is now on to the third, where she will face Anna Kalinskaya.

ANDREESCU HOLDS OFF RISKE

Former US Open champion Bianca Andreescu saw a potential straight-sets win slip away before recovering to defeat Alison Riske 7-6 (7-2) 5-7 6-2.

Andreescu – the defending champion after the 2020 WTA Premier 1000 event was cancelled due to the coronavirus pandemic – led 4-1 in the second set but watched her advantage evaporate as Riske forced a decider, which the Canadian ended up taking comfortably as she faced only one break point in the last. 

Top seed Karolina Pliskova eased past Magdalena Frech 7-5 6-2, while third-seeded Barbora Krejcikova was pushed to a third set before prevailing 6-4 3-6 6-1 against Zarina Diyas. 

Angelique Kerber – the 10th seed and three-time major winner – went the distance to beat Katerina Siniakova 6-1 6-7 (4-7) 7-5, while 15th seed Coco Gauff downed Caroline Garcia 6-3 6-7 (2-7) 6-1 in her debut match at the tournament. 

Ons Jabeur, the 12th seed, prevailed 6-2 6-7 (5-7) 6-3 over Anastasija Sevastova and 18th seed Anett Kontaveit – Andreescu's next opponent – moved on when Martina Trevisan retired down 6-3 5-2. 

Osaka's serve was sharp and it carried her through the match, with 11 aces to Zheng's three, while giving up one break of serve and securing three breaks herself.

After Zheng fought back to win the second set, Osaka was the steady head in the decider, allowing her opponent to implode with three double-faults in crucial points to collect her first win since April.

Osaka will meet Cori Gauff in a star-studded second-round matchup after Gauff dominated Anhelina Kalinina 6-1 6-0.

She was simply too powerful for her Ukrainian opponent, winning 89 per cent (25-of-28) of her first serves to never give Kalinina a chance.

Canada's Bianca Andreescu was eliminated by American Shelby Rogers 6-4 6-2, while Russia's Veronika Kudermetova won a hard-fought battle against Italy's Camila Giorgi 7-6 (7-2) 4-6 7-5.

Meanwhile, in Washington at the Citi Open, Emma Raducanu looked in good touch as she handled the challenge of Louisa Chirico 6-4 6-2 to advance to the second round.

Raducanu will meet Colombia's Camila Osorio after she beat American Sofia Kenin 7-6 (7-2) 6-1, and top-20 talent Victoria Azarenka had no issues against Dayana Yastremska to win 6-4 6-0.

Australian Ajla Tomljanovic continued her strong run of form with a convincing 6-1 6-4 win against American Sloane Stephens, and the Czech Republic's Tereza Martincova recovered from a horrible first set to defeat Xinyu Wang 0-6 6-4 6-4.

Germany's Andrea Petkovic cruised to a 6-2 6-2 win against Denmark's Clara Tauson, and Russia's Anna Kalinskaya defeated American Madison Brengle 6-3 6-0.

Osaka's match was interrupted by rain early on with her in the lead, but Andreescu came back out in top form to take the first set.

The Japanese raced through the second though, taking a 5-0 lead before holding off Andreescu's fightback to go into a decider.

Despite an impressive comeback to force a tie-break in the final set, Osaka became sloppy, with her mistakes contributing to the Canadian's path into the semi-final, where she will face Dalma Galfi.

Elsewhere, Alex de Minaur is through to the semi-finals after a comfortable straight-sets victory over Milos Raonic.

Despite a long break due to bad weather, the Australian eased into the next round with a 7-5, 6-2 victory on Friday.

He will face either Ugo Humbert or Gijs Brouwer in the next round.

Data Debrief: Osaka not close enough, De Minaur in cruise control

Despite winning more points (98 compared to 94), and winning more games (16 to 15), Osaka could not hold her nerve in the tie-break to reach the semi-finals.

Competing as the top seed for the first time in his tour-level career, De Minaur felt no pressure as he rallied in the second set to ensure Raonic would not find a way back into the match, winning his last five games in a row on his way to victory. 

Four-time grand slam winner Osaka crashed to a resounding 6-3 6-1 loss to Spain's Sara Sorribes Tormo, exiting her first tournament on clay since the 2021 French Open, where she withdrew citing mental health issues.

Osaka, who had posted an underwhelming 20-15 record on the surface prior to this week, looked uncomfortable throughout and appeared to struggle with a leg injury during a disappointing second set display.

The 24-year-old was not the only high profile player to be on the receiving end of a shock during a day of drama in the Spanish capital, as several of the competition's seeds failed to secure places in the last 16.

Another home favourite, Garbine Muguruza, fell to a resounding loss of her own as Anhelina Kalinina raced to a 6-3 6-0 victory over the seventh seed, while sixth seed Danielle Collins was thrashed 6-1 6-1 by Canadian Bianca Andreescu.

Fourth seed Maria Sakkari was the highest-ranked player in action, and although the world number five won the first set of her clash with Daria Kasatkina, the Greek eventually fell to a 3-6 6-3 6-1 loss, while 2021 US Open runner-up Leylah Fernandez went down 6-4 6-4 to Jil Teichmann.

One big name who did make comfortable progress, however, was Fernandez's US Open conqueror Raducanu, who eased to a 6-2 6-1 win over Kostyuk to set up a last-16 encounter with another Ukrainian in Kalinina. 

The 19-year-old, who has been quoted as saying she believes clay could prove to be her best surface in the future, was delighted with her victory and enjoying the tournament after dropping just one game in the second set.

"I'm definitely happy with my performance," Raducanu said on court. "Marta's a great opponent - I knew it was going to be a really tough battle. I went out there trying to be really aggressive and it paid off.

"It's my first clay court season and I'm really enjoying it. Madrid is such a cool city and it's got such a great vibe about it. I definitely want to try and stay here for as long as possible."

The former world number one has not played on the red dirt since the 2021 French Open, where she withdrew citing mental health issues.

Heading into this week in Madrid, Osaka had an underwhelming 20-15 record on clay, with each of her grand slam successes coming on hard courts.

But the 24-year-old has spoken of adjusting her approach and learning from clay king Rafael Nadal – and the early signs were positive.

She needed just over an hour to defeat Potapova 6-3 6-1 on Friday and said: "I'm honestly trying to be more positive with myself.

"This year I came a week early to train on red clay, so I'm just trying to give myself more chances to do better.

Osaka added: "To be able to do it in two sets, for me, it's a really good starting block. 

"I think today for me it was really fun, just being able to be back on the clay and not taking those moments for granted."

Fellow hard-court major champions Emma Raducanu and Bianca Andreescu also won their openers, although the latter required three sets to eventually coast past Alison Riske 6-4 3-6 6-0.

Raducanu will play another 19-year-old in the second round, with the US Open champion paired with Marta Kostyuk after getting over a slightly slow start to thrash Tereza Martincova 7-6 (7-3) 6-0.

Fourth seed Maria Sakkari overcame a scare, meanwhile, ending her losing run at three matches by coming from behind to defeat Madison Keys in three sets.

"Overall, it was a very positive match to get myself back in the winning feeling," the Greek said.

Osaka, who lost in the final round of qualifying for the Cincinnati Open, won the first of her four grand slam titles at Flushing Meadows in 2018, winning again two years later. 

The former world number one returned to the tour this season after giving birth last year, but has struggled to find the form that led her to climb to the top of the rankings. 

The Japanese is now ranked 90th in the WTA rankings, with her best finishes coming in Doha and 's-Hertogenbosch where she reached the quarter-finals in both. 

She will be joined in the women's singles by Canada's Andreescu, who was crowned the US Open champion after her win over Serena Williams in 2019. 

The 24-year-old returned to action this year after missing nine months due to a back injury and reached the French Open third round in her first event back.

Meanwhile, Thiem headlines the wildcards in the men's singles in what will be the final grand slam of his career after confirming he will retire at the end of the season. 

The Austrian won the US Open in 2020 in an epic five-match thriller against Alexander Zverev, but has failed to his best form after sustaining a wrist injury three years ago. 

Also returning thanks to a wildcard is Wawrinka, eight years on from when he claimed the title in New York against Novak Djokovic at Flushing Meadows. 

The 39-year-old's triumph in the United States was the latest of his three career grand slams, having previously prevailed at the Australian Open and French Open. 

Australian Open champion and second seed Osaka benefited from a walkover after qualifier Nina Stojanovic withdrew ahead of Sunday's clash due to a right thigh injury.

Elise Mertens will face Osaka following the 16th seed's 6-2 0-6 6-2 win against Anett Kontaveit.

Two-time grand slam winner Muguruza rallied past Russian wildcard Anna Kalinskaya at the WTA Premier event.

However, fourth seed Kenin was sent packing as sixth seed Pliskova was tamed by nemesis Jessica Pegula in Miami.

MUGURUZA STAYS HOT

Spanish star Muguruza dug deep to earn her tour-leading 20th win of the season.

Former world number one Muguruza – the 12th seed – prevailed 4-6 6-3 6-4 against Kalinskaya, having trailed 3-0 in the final set.

"I brought my fighting spirit and I could match the level of fighting against Anna, and very happy to go through these tough matches," Muguruza said following two hours, 41 minutes on court.

"Doesn't matter if you play pretty or you play ugly, but you stay strong and you go through these rounds. That gives me an opportunity to feel better and to have another chance."

Muguruza – who has the most final appearances this season with three, having won the Dubai Tennis Championships and finished runner-up at the Qatar Open and Yarra Valley Classic – will next face eighth seed Bianca Andreescu.

Former US Open champion Andreescu overcame fellow seed Amanda Anisimova 7-6 (7-4) 6-7 (2-7) 6-4.

KENIN'S WOES CONTINUE

It has been a rough 2021 for American star Kenin.

Stunned in the second round of the Australian Open – in her title defence – Kenin then crashed out of the Phillip Island Trophy at the first hurdle.

Kenin rallied to beat Andrea Petkovic first-up in Miami, but the 22-year-old was beaten 6-4 4-6 6-4 by 27th seed Ons Jabeur.

Jabeur and Sara Sorribes Tormo – who shocked 21st seed Elena Rybakina 6-1 3-6 6-2 – will meet for a spot in the quarter-finals.

PLISKOVA FALLS TO PEGULA… AGAIN

For the third time this past month, 2019 Miami Open runner-up Pliskova went down 6-1 4-6 6-4 to 29th seed Pegula.

Australian Open quarter-finalist Pegula conquered Pliskova in Doha and Dubai before repeating the feat in Miami on Sunday.

"I played her a lot the last three weeks, three tournaments," Pegula said. "I kind of expected her to play well there. Even when I was up I still felt like she could easily come back just because she plays so aggressive and she serves well."

After reeling off the final four games, Pegula set up a last-16 showdown with 23rd seed Maria Sakkari, who dismantled qualifier Liudmila Samsonova 6-0 6-1.

The four-time major winner took just 54 minutes to wrap up a 6-2 6-2 win over her Dutch opponent in t'Hertogenbosch.

Osaka looked sharp as she sought her second WTA quarter-final appearance of the season, having also reached that stage in Doha four months ago.

The Japanese hit 21 winners to 13 unforced errors, while converting four out of five break points against the world number 140.

Next up for Osaka is a showdown with 2019 US Open champion Andreescu in the last eight.

Data Debrief: Osaka storms into first grass-court quarter-final in six years

It was a dominant display by Osaka, who hit nine aces and won 15 of her 17 points on first serve (88.2 per cent).

The four-time major winner subsequently advanced to her first WTA quarter-final on grass since the 2018 Nottingham Open.